The UAB MCRC is a multidisciplinary program uniquely positioned to promote research related to the causes, diagnoses, treatments and improved care of patients with arthritis and musculoskeletal diseases. The MCRC builds on the capabilities of the UAB Comprehensive Arthritis, Musculoskeletal, and Autoimmunity Center (CAMAC) and its thematic workgroups (Experimental Therapeutics & Biomarkers; Neurobehavioral Medicine; Epidemiology, Prevention, & Outcomes; Genetics and Functional Genomics; Immunology, Autoimmunity & Inflammation; Bone, Cartilage and Connective Tissue). An outstanding MCRC Methodology Core is comprised of experts in biostatistics (Redden, Howard, McGwin, Aslibekyan), data management (Westfall), statistical genetics and bioinformatics (Cui, Lefkowitz, Liu) and health services research (Kilgore). All have a proven record of collaborative clinical investigation in musculoskeletal diseases. This proposal includes 3 innovative projects: 1. Genetic Determinants of Cell Type-Specific Gene Expression in RA (Brown/Bridges); 2. Facilitating Treat-to-Target Strategies Using Novel Health Technology with Decision Support (Curtis); 3. Adaptive Immune Responses to Gut Microbiota in Juvenile & Adult Spondyloarthritis (Elson). Projects 1 and 3 focus on populations for which there is a paucity of clinical research: (African-Americans with RA and juvenile spondyloarthritis). All projects leverage and expand upon substantial existing resources, including ongoing cohorts. The Administrative Core coordinates MCRC activities, sets the strategic agenda, facilitates interactions and collaborations, promotes scientific development, and performs evaluation of MCRC programs. Four advisory groups have been established to assist the MCRC Director and Associate Director in maximizing the strengths of the MCRC's projects, as well as in identifying and correcting weaknesses: 1. Executive Committee; 2. Internal Advisory Committee; 3. External Advisory Committee; 4. Data Safety Monitoring Committee. The Scientific Development Program, which promotes the introduction and development of new techniques and nurtures young and new faculty in arthritis and musculoskeletal disease research, ensures the continued energy and vitality of this MCRC.